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Re: "git gc" doesn't seem to remove loose objects any more

From
Jakub Narebski <jnareb@gmail.com>
Date
Dec 15, 2008, 17:07 UTC
Message-ID
<m3vdtlcqp6.fsf@localhost.localdomain>
In-Reply-To
<20081215155610.GA11502@mit.edu>
Theodore Tso <tytso@mit.edu> writes:
> On Mon, Dec 15, 2008 at 03:08:34PM +0100, Björn Steinbrink wrote:
Show 23 quoted lines
> > To clarify that a bit more: git gc keeps unreachable objects unpacked,
> > so that git prune can drop them. And git gc invokes git prune so that
> > only unreachable objects older than 2 weeks are dropped.
> 
> To be even more explicit, "git gc" will **unpack** objects that have
> become unreachable and were currently in packs.  As a result, the
> amount of disk space used by a git repository can actually go **up**
> dramatically after a "git gc" operation, which could be surprising for
> someone who is running close to full on their filesystem, deletes a
> number of branches from a tracking repository, and then does a "git
> gc" may get a very unpleasant surprise.
> 
> A really good repository which shows this is linux-next, since it is
> constantly getting rewound, and old branches are reserved via a tag
> such as next-20081204.  If you update the your local copy of the
> linux-next repository every day, you will accumulate a large number of
> these old branch tags.  If you then delete a whole series of them, and
> run git-gc, the operation will take quite a while, and the number of
> blocks and inodes used will grow significantly.  They will disappear
> after a "git prune", but when I do this housekeeping operation, I've
> often wished for a --yes-I-know-what-I-am-doing-and-it's-unsafe-but-
> just-drop-the-unreachable-objects-cause-this-is-just-a-tracking-repository
> option to "git gc".

There was an idea to have "git gc --prune" run "git prune" unconditionally, i.e. without grace period for dangling loose objects.

-- 
Jakub Narebski
Poland
ShadeHawk on #git
Previous: Mikael MagnussonNext: Theodore Tso
Message 9 of 12 in “"git gc" doesn't seem to remove loose objects any more”
  1. Bruce StephensDec 15, 2008
  2. Mikael MagnussonDec 15, 2008
  3. Bruce StephensDec 15, 2008
  4. Björn SteinbrinkDec 15, 2008
  5. Theodore TsoDec 15, 2008
  6. Mark BrownDec 15, 2008
  7. Johan HerlandDec 15, 2008
  8. Mikael MagnussonDec 15, 2008
  9. Jakub NarebskiDec 15, 2008
  10. Theodore TsoDec 15, 2008
  11. Brandon CaseyDec 15, 2008
  12. objects to be pruned immediately don't have to be loosenedNicolas Pitre, Dec 15, 2008

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